Abstract 9405: Lower Achieved Systolic Pressure (=130 mm Hg) is Associated With a Decreased Risk of New Atrial Fibrillation in Hypertensive Patients With Electrocardiographic Left Ventricular Hypertrophy: The LIFE Study

Abstract

Background: There is a well-established association between hypertension and atrial fibrillation (AF), with recent studies demonstrating that even upper normal systolic blood pressures (SBP) are long-term predictors of incident AF. These findings suggest that more aggressive control of BP may reduce the risk of new AF. However, whether more aggressive reduction of SBP is associated with a lower incidence of AF remains unclear. Methods: Risk of new-onset AF was examined in relation to last in-treatment SBP prior to AF diagnosis or last in-study measurement in the absence of new AF in 8831 hypertensive patients with ECG LVH with no history of AF, in sinus rhythm on their baseline ECG, randomly assigned to losartan- or atenolol-based treatment. Patients with in-treatment SBP ≤130 mm Hg (lowest quintile at last measurement) and SBP between 131 and 141, were compared with patients with in-treatment SBP ≥142 (median SBP at last measurement). Results: During 4.6±1.1 years follow-up, new-onset AF was diagnosed in 701 patients (7.9%). In univariate analyses, compared with in-treatment SBP ≥142, in-treatment SBP ≤130 entered as a time-varying covariate was associated with a 46% lower risk (95% CI 31-58%) and in-treatment SBP between 131 and 141 with the same 46% lower risk (95% CI 35-55%) of developing AF. After adjusting for randomized treatment, age, sex, race, diabetes, history of ischemic heart disease, MI or heart failure, prior antihypertensive therapy, baseline serum glucose, creatinine, HDL and total cholesterol entered as standard covariates, and for incident MI, heart failure and in-treatment Cornell product LVH, heart rate, diastolic BP and HDL treated as time-varying covariates, achievement of a SBP ≤130 remained associated with a 40% lower risk (95% CI 18-55%) and in-treatment SBP of 131 to 141 with a 24% lower risk (95% CI 7-38%) of new AF. Conclusions: Achieved SBP ≤130 is associated with a lower risk of developing new-onset AF in hypertensive patients with ECG LVH, independent of other known and possible risk factors for AF. Further study will be needed to determine whether targeting hypertensive patients without AF to lower SBP goals can reduce the burden of new AF in this high-risk population.